To facilitate the cleaning of a brush material after coating is finished and to improve the retention of coating at reuse after cleaning by affording water repellency to the brush material in a roller brush for coating comprising the brush material and a core material which is used for coating a plate for building.

A roller brush 10 for coating, which is fitted to a manual coating handle and a coating machine and used for coating a building material and others, is composed of a core material 11 and a water-repellent brush material 15 installed on the periphery of the core material 11. The core material 11 is formed in the shape of a cylinder of a prescribed size by using a synthetic resin, paper, metal, or the like. The brush material 15 is formed cylindrically by using a sponge material such as rubber and a urethane resin and a chemical or natural fiber material and others, and a water repelling agent such as paraffin and a petroleum resin is adhered to the material 15 to make it water- repellent. In this way, the brush material 15 is cleaned easily, and the retention of coating at reuse after cleaning is secured well.